Apparatus for excavating trenches



Sept. 16, 1969 G. NOVET 3,466,769

APPARATUS FOR EXCAVATING TRENCHES Filed March 23, 1966 2 Sheets-Sheet 1 J INVENTOR Md W ATroRNES' APPARATUS FOR EXCAVATING TRENGHES Filed March 23, 1966 2 Sheets-Sheet z INVENTOR qwuww BY )QMA W ATTORNEK United States Patent Int. Cl. E02 /02, 9/00 US. Cl. 37103 1 Claim ABSTRACT OF THE DISCLOSURE Apparatus for excavating trenches includes a pair of vertical piles each having a guide rib thereon, adapted to be driven in parallel relation into the soil; a vertically movable chassis provided with upper and lower grooved guide rollers yieldably engaging the guide ribs; a grab bucket suspended below said chassis; cable means for suspending said chassis; outwardly divergent rails forming an upward extension of the guide ribs above the soil; scrapers on the chassis disposed adjacent each lower roller engaging their respective guide ribs; and brushes on the chassis disposed adjacent each upper roller engaging their respective guide ribs; the chassis, grab bucket, scrapers and brushes being all of same width as the trench which is excavated by the apparatus.

The present invention relates to a new apparatus for the digging of trenches, principally with a view to excavating deep narrow trenches intended for the placing of a wall embedded in the earth.

According to this invention a method of excavating trenches comprises the steps of implanting two vertical piles in the soil each of these piles having a guide face on which there rolls an excavating machine formed by a chassis fitted with a bucket grab, and lowering the machine into the ground on the piles while operating the bucket grab. The guiding of the machine is preferably ensured by flexibly mounted rollers on the chassis, hearing on opposing faces of the two piles. Finally, to facilitate the placing of the machine there are provided above the level of the soil divergent guide rails which meet the roller faces of the piles.

One construction of a machine in accordance with the invention and its method of use will now be described by way of example only with reference to the accompanying drawings in which:

FIGURE 1 is an assembly view illustrating two possible positions of a machine according to the invention,

FIGURE 2 is a plan view of the machine shown in FIGURE 1, and

FIGURE 3 is an end view of the machine.

According to the object of the invention, it is proposed to excavate a deep trench of which the width 1 (FIG- URE 2) does not exceed that of a Wall or similar construction which it is desired to pour directly into the soil. It will especially be seen that this limits earth movement to the strict minimum and abolishes any unnecessary operation of excavation or filling in.

To carry out the invention, the first step is to implant vertically in the soil two concrete piles A of known type, which extend to the full depth desired for the trench.

Each of the piles A is preferably made with a cruciform shape and their opposing faces are furnished with a sheath of sheet metal 2 forming a roller rail of semicircular crosssection.

At its upper part, each pile A carries in the conventional manner one or more transverse holes 3 which are used to mount draw bolts 4, ensuring the fixing of a 3,466,769 Patented Sept. 16,, 1969 framework 5 on the top or the aforementioned piles A. The framework 5 rests on the soil and it supports two rails 6 which diverge upwards and at their bases register with the sheet metal sheaths 2 of the piles A. The rails 6 are arranged in the vertical plane which is fixed by the axes of the two piles A. These rails 6 are rigidly held at their tops by a frame 7.

The assembly of the rails 6 and the sheet metal sheaths 2 constitutes a metal roller-way 2-6, which is used to ensure the guiding of an excavating machine which will now be described in detail.

The excavating machine in question includes a chassis 8 which is suspended from a manipulating cable 9 of which the control is ensured from the exterior of the trench by any known means. These means may consist of a winch, a crane or any contracting machine whatever.

The chassis 8 is provided with four guide rollers arranged in symmetrical pairs on each side of its vertical axis, that is to say, two upper rollers 10 and two lower rollers 11. Each roller 10 or 11 is mounted free in a supporting fork 12 which is attached to a stem 13 able to slide horizontally against a compression spring 14 in a seating provided for it in the chassis 8.

Each roller 10 or 11 has a groove 15 (FIGURE 3) with a profile of the arc of a circle which allows it to run along the rails '6 or the sheet metal guides 2.

The assembly is of dimensions such that the springs 14 are always compressed when the machine is placed between two piles A on which it rolls on its rollers 10 and 11 (FIGURE 1).

There is provided below each lower roller 11, a metal shoe 16 of which the tip is shaped exactly to fit the external contour of the corresponding roller-way 2-6, which it thus scrapes so as to remove from it any grit or deposits which may harm the smoothness of rolling. Similarly, there is placed immediately below each upper roller 10, a metal brush 17 intended to complete the cleaning of the appropriate roller-way 2-6.

At the lower end of the chassis 8 there is suspended a hydro-electric bucket grab 18 of known type, of which the automatic or semi-automatic action is controlled from the outside. This bracket 18 principally includes two jaws 19 jointed about transverse spindles 20.

Finally, the chassis 8 of the machine is suspended from the cable 9 by means of a block 21 which may be aligned in any required direction in relation to the chassis 8 then locked in any position whatever.

The working is as follows:

When the machine is in a state of rest, that is to say positioned outside the roller-way 2-6, the lateral displacement of the rollers 10 and 11 in the direction of the arrows 22 (FIGURE 1) is checked by stops which are not shown.

When the chassis 8 is lowered into the position 801 shown in FIGURE 1, the machine begins to come into contact with the rails 6 by its lower rollers 11 which contract in the direction opposite to that of the arrows 22. When the machine is further lowered, the upper rollers 10 enter in their turn into contact with the rails 6, then in proportion as the level of the soil is approached, the various springs 14 are compressed finally to hold the rollers firmly applied against the sheet metal sheaths 2 when the machine is engaged between the piles A. The shoes 16 and the brushes 17 each being mounted on the fork of the corresponding roller, it will be seen that these accessories remain in constant contact with the corresponding part of the roller-way 2'6, whatever may be the shape of the latter, principally in the case of the divergent entry rails 6 shown in FIGURE 1. There is thus ensured a complete cleaning of the rolling faces at every point of the guides.

When the jaws 19 come into contact with the soil, the bucket grab 18 is operated in the usual manner so as to take a load of earth which is then raised by means of the cable 9 before tipping it out of the trench.

It will be seen therefore that the operation of a machine according to the invention is similar to that of a bucket grab of conventional type, while the guiding is automatically ensured by the chassis 8 and its accessories.

In addition, if care is taken to construct the machine assembly, including its chassis 8, and the jaws 19 of the bucket grab 18, with a width which does not exceed the width 1 of the proposed trench, it will be understood that the process according to the invention permits the reduction of earth movement to a strict minimum.

According to a means of construction preferred by the invention, the shoes 16 and the metal brushes 17 are given a width equal to that of the jaws 19 of the bucket grab (FIGURE 3).

While in the above specific description the piles A are shown extending to the full depth of the trench to be excavated, it should be understood that it may in some instances be suflicient to arrange them deep enough to allow the rollers 11 to descend enough to allow the grabs 19 to cut out the required depth.

I claim:

1. Apparatus for excavating trenches comprising a pair of vertical piles each having a guide rib thereon, adapted to be driven in parallel relation into the soil; a vertically movable chassis provided with upper and lower grooved guide rollers yieldably engaging said guide ribs; a grab bucket suspended below said chassis; cable means for suspending said chassis; outwardly divergent rails forming 4 an upward extension of the guide ribs above the soil; scrapers on the chassis disposed adjacent each lower roller engaging their respective guide rib; and brushes on the chassis disposed adjacent each upper roller engaging their respective guide ribs; the chassis, grab bucket, scrapers, and brushes being of same width as the trench which is excavated by the apparatus.

References Cited UNITED STATES PATENTS 451,165 4/1891 Zimmerman 37194 477,518 6/ 1892 'Cronkhite 37-194 910,277 1/1909 Eliel et al 37-61 1,008,727 11/1911 McCarthy 6141 1,356,008 10/1920 Phillips. 1,352,852 12/1920 Dabis 61-59 XR 2,194,134 3/1940 Berryman et a1 187-96 2,426,591 9/1947 Boskovich 29967 XR 3,054,447 9/1962 Brydolf 1696 XR FOREIGN PATENTS 1,058,454 6/ 1959 Germany. 1,246,459 10/ 1960 France.

ROBERT E. PULFREY, Primary Examiner CLIFFORD D. CROWDER, Assistant Examiner US. Cl. X.R. 

